English city lacking old English fibre (7)

I believe the answer is:

bristle

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'fibre' is the definition.
(bristle is a kind of fibre)

I don't understand how the remainder of the clue works.

(Other definitions for bristle that I've seen before include "React angrily" , "Stand up" , "Stiff fibre" , "A short stiff hair, as in beard" , "Look angry" .)

I've seen this clue in The Times.

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